Matthew, it's hard to 4-bet light because all the players on Zone are anonymous. If I had stats that show they are capable of 3-betting light, are constantly 3-betting my CO/BTN raises, and have reggist stats indicating they are not going to spew and call with 75o/mid PP OOP, I do 4-bet light with Axs hands to get them off my back. I've done this a few times in cash games, but you never know what's going to happen in Zone because they do a lot of spewy stuff. It's much easier to say than do maximizing +EV spots, even very marginal ones, at the cost of super high variance. Imagine playing in the actual high stakes poker game
like 2kNL. 5-betting jamming light in this one particular spot always nets a +EV of 0.5/100bb, but you can just fold instead to reduce variance. This idea is mentioned in some articles explaining some other ways professional poker players attempt to reduce their variance. The money factor and tilt does sink in much harder from variance and losing once you play higher and higher. The reward doesn't really outweigh the risks.
Iplay, the graph was all-in KK preflop only. KK had something like low 50% all-in equity against a stackoff range. He didn't count postflop. He'd be a terrible player if he couldn't find an overall winning with KK.
Bitowl, I've never folded KK pre. I have had many times where I was pretty certain he had AA and wanted to fold, but I always end up shipping it in <120BB to see AA pretty often. Deep-stacked 150-200+BB I flat the 3-bet/4-bet and sometimes 4-bet depending on reads and on my position.
Like a fishy guy min 3-bets you MP vs your UTG open, and you come over the top with a huge 4-bet. He then min 5-bets you, and you hold KK. Are you happy with shipping it in? I wasn't, but I shipped it in and obv he had AA. In Zone, you're 160bb deep, and you barely cover another (probable) reg. You 3-bet in MP vs UTG, and he 4-bets you. You happy with KK? I flatted IP and went broke obviously. There are many situations that come up where I'm 90% sure they have AA, and I always read that you can't fold KK preflop in 6-max. Following that advice, I ship it in and go broke a decent amount.
At Bovada or live where your stats cannot be tracked, having exploitable ranges is the most profitable way to go. If you know someone's stack-off range is only KK+, then you cannot call off with less than AA. And if people call your 3-bets and 4-bets light, the most profitable way is to go with 3-betting/4-betting for pure value. Why be unexploitable when the most profitable way is to by exploiting someone else's weaknesses? 3-betting/4-betting an unexploitable range for the sake of being unexploitable is spew and not more +EV than having an exploitable range at the low stakes/micros where other people are typically unbalanced. Having unexploitable ranges is really only required when you are playing against regs who have super balanced ranges, and when these regs have stats on you. Sure, if I play on Pokerstars and play against nerdy GTO opponents who can see my stats, I will adjust to have unexploitable ranges so they can't 4-bet/5-bet light and take advantage of me.